Average weight to length ratio?

[mattyd]

Hi
I weighed my tort for the first time a number of weeks ago after reading that it's important to know your tortoise gains weight ok.
Does anyone know of any ratio or average weight of tortoises at centre lengths or ages?

Thanks

 

[Tom]

Any "average" is meaningless as they all grow at different rates for a very wide variety of reasons. I have 8 month old russians that are larger than their 16 month old siblings from the same parents and living together in the same enclosure eating the same food.

Just look for nice steady weight gain in YOUR tortoise and don't worry about the rate. Give a good species appropriate diet, correct temps, good hydration, lots of exercise and sunshine if possible in your area, and let him grow however fast he grows.

Here is a russian care sheet, in case you are interested: http://www.tortoiseforum.org/thread-80698.html

 

[tortoise5643]

Re: RE: Average weight to length ratio?

Any "average" is meaningless as they all grow at different rates for a very wide variety of reasons. I have 8 month old russians that are larger than their 16 month old siblings from the same parents and living together in the same enclosure eating the same food.

Just look for nice steady weight gain in YOUR tortoise and don't worry about the rate. Give a good species appropriate diet, correct temps, good hydration, lots of exercise and sunshine if possible in your area, and let him grow however fast he grows.

Here is a russian care sheet, in case you are interested: http://www.tortoiseforum.org/thread-80698.html

I THINK he meant like for example if a tortoises is 8in then it should way 1 pound (thats not real I just made it up)

I'm not really sure though, I might have read it wrong, I have a tendency to do that

 

[AnnV]

They have a formula for horses. It is more to guestimate weight because horses can't be weighed easily. I dont need to do so myself, because our town transfer station, 1\4 mi down our road, allows us to walk the horses over and weigh them.
But since most horses are built similarly, you can get close (for purposes of worming, etc) by using a formula involving measuring their girth and length.

I think the OP would like to know if there is a formula such as this for tortoises, so when the tort is weighed, it can be determined if said tort fits into a proper average.
But I would imagine that torts are built too deferently from one another, to come up with a universal average.

 

[Cowboy_Ken]

AnnV, I agree completely. Also, with a horse growing faster, and a tortoise surviving a long time in poor conditions while not growing and all, I would think anything would be a guess at the best.

 

[bettinge]

What kind of tortoise are we talking about? For Mediterranean torts (Greek, Hermanns, Marginated) there is what's called "The Jackson Ratio"! It can give you an idea if your tort is under weight, over weight, or about right. It's a weight to length (SCL) ratio. There are a few limitations where it can give false readings, but in general is a nice tool.

The Jackson Ratio does not Apply to species other than the Mediterranean ones. Here is a link to the calculator.

http://www.tortoise-protection-group.org.uk/site/171.asp

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Oops, I just read the limitations. It does not specifically mention Marginated tortoises. I should think its very close, but you might have to a bit more homework if you have a Marginated.

 

[mattyd]

My tort is a horsfield not entirely sure but think its a female , and I read recently that there was some sort of formula , think your right with the Jackson formula thing , I was wondering if there was a weight that is sort of seen as a good weight or of a tortoise is underweight etc

 

[biochemnerd808]

As a rule of thumb, your tortoise should feel heavier than it looks. You can weigh it every month or two on a digital postal scale, and write down the weight in a notebook. This way you can see if there is gain or loss.

The Jackson's ratio doesn't apply to horsfields tortoises (Russian tortoises), because it doesn't take the different body shapes into account.

Joe Heinen (who wrote www.russiantortoise.net) has a formula that he has tested out over the last 30 years, and that works well. It will give you the goal weight of a tortoise the size of yours, so you can see if yours is close to this.

[length (cm) x width (cm) x height (cm)] x 0.57 = ideal weight in grams.

To measure your tortoise's length, width and height, you need to measure the LINEAR length, book-end style, NOT over the curved top. You can do this by placing your tortoise ON a ruler, up against the wall for the length and width, and for the height, by holding the ruler upright, and using a balance (or in a crunch, a book) to determine the linear height.


I've tested this formula on my 6 RTs and several rescue RTs, and have found it to be accurate. I hope this helps!